Smoke-consuming furnace.



No. 717,934. i PATENTBD JAN. s, 1903.] 0.1J. SHOEMAKER;

SMOKE UONSUMING FURNAGE.

APPLICATION FILED MAB.. 26, 1902. N0 MODEL. m m 3 SHEE'lA-S `EI'l l.

ich v2 M A WITNESSES: lNI/ENTOR.

5,4 TTOJeN/fx 1H: Nonals PETERS co.. Immo-mmm wAsHmcroN, n. c.

10.717,934. PATENTBD JAN. 6, 1903.

G. J. SHOEMAKBR. SMOKE GONSUMING FURNAGB.

APPLICATION-FILED MAL-26, 1902.

NO MODEL. 3 SHEETS-SHEET 2.

4S y w uw# WITNESS/Es: Y V JNVENTOR.

'Unfreie STATES PATENT OFFICE.

CHARLES J. SHOEMAKER, OF INDIANAPOLIS, INDIANA.

sMoKfE-coNsuMlNc FURNACE.

SPECIFICATION forming part of Letters :Patent No. 717,934, dated January 6, 1903.

` Application aiednmt 20,1902.

To @ZZ whom it may concern.: y

Be it known thatl, CHARLES .1.SH0EMAKER, of Indianapolis, county of Marion, and State of Indiana, have invented a certain new and useful Smoke-Gonsuming Furnace; andl do hereby declare that'thefollowing is a full, clear, and exact description thereof, reference being had to the accompanying drawin gs,in whichlike numerals refer to like parts. The object of this invention is to improve the construction of furnaces, preferably for steam or other boilers, that will cause the smoke to be consumedby the furnace, and thus prevent the discharge of smoke from the smoke-stack, as well as gain the increased heat that results from consuming the smoke. One feature of the invention consists in means for returning the smoke from the smoke-conduit to the furnace-chamber and mixing air and steam with the smoke and unconsumed gases at or near the point where the return-conduit leaves the smoke-condull. 1 i' i Another feature of the invention consists in 1 rovidinvasu lementar or mixinor chamber for an induced draftfbehind the ashpit or chamber,through which the natural draft passes, and separating such` chambers by a partition provided with closed openings through which the ashes may be removed from said supplementalor rear chamber.

Another featureconsists in providing the bridge-wall immediately at the rear of the furnace-chamber with a i horizontal forwardprojecting arch extending` over said supplemental chamber and having an opening through the bridge-wall immediately below said arch.

Another feature consists in combining with the` two chambers beneath the gratebars, through one of which there is a natural draft and through the other an induced draft,n1eans for introducing a draft above the grate-bars to cause said natural and induced drafts to meet and commingle.

The various features of this invention will be understood from the accompanying drawings and the following description and claims.

In the drawings, Figure 1 is a central vertical longitudinal section through a furnace of the class mentioned, showing the boilers and pipes above in side elevation with the serai No. 100,088. (No model.)

smoke-stack broken away. Fig. 2 is a verticalcross-section on the line 2 2 of Fig. 1, showing a battery of two boilers and looking forwardly from the section-line. Fig. 3 is a `vertical cross-section on the line 2 2 of Fig. 1 `looking rearward instead of forward. Fig. 4 is a central vertical sectionthrough the smoke-conduit above the boiler and i the return-pipe leading therefrom online 4 4 of Fig. 5, parts being broken away, as shown. Fig. 5 is a cross-section on the line 5 5 of Fig. 4. Fig. 6 is a front elevation of the damper and a portion of the smoke-conduitshown in Fig. 4.1 Fig. v7 is a plan view of the means for introducing a draft above the grate-bars `in the furnace-chamber, the `forward wall of the furnace being shown in horizontal section on theline '7 7 of Fig. l.

The furnace construction shown in the drawings to illustrate the natureof my invention consists of two boilers A10, suitably `inountedin a furnace having the side walls l1, the rear wall 12, the front wall 13, and a central longitudinal wall;14, the latter separating the two boilers and the chambers below. Under the forward portion of said boilers the furnace-chambers are arranged between the front wall 13 and the forward bridge-wall 15, said furnace-chambers consisting of three chambers-the fire-box 16 above the grate-bars 17, the ash-pit or natural-draft chamber 18 below the forward portion of the grate-bars, and a supplemental or mixing chamber 19 to the rear of the ashpit and below the rear portion of the grate-bars. The chambers 18 and 19 are separated by a partitional wall 20, having in it large openings through which a natural draft may pass, if desired, and throughnvhich ashes may be removed from the rear chamber 19 into the forward ash-pit 1S. These openings through the wall 20 are closed tight by doors 21. The openings in the lower part of the front wall 13 are provided to remove the ashes from the ash-pit and for the passage of natural draft therethrough, said openings being controlled by the doors 22. Suitable openings are also provided through the front wall for giving access to the fire-box, said openings being closed by the doors 23. Arches 24 are built above the rear portion of the grate-bars and project forward horizontally from the upper ing or controlling the saine.

part of the bridge-wall 15. These arches eX- tend forward far enough to cover about half of the portion of the grate-bars over the supplemental or rear mixing-chamber 19, substantially as shown in Fig. 1. The purpose of these arches is to deiect the major portion of the gases arising from the chamber 19 and the fire above it forward and upward against the boiler and over the arches and bridge-wall, substantially as indicated by the arrows. In order to increase the draft somewhat, openings 25 are made in the upper part of the bridge-wall under said arches 24, the dimensions of said openings being comparatively small, so as not to interfere materially with the function of the arches.

26 is a rear bridge-wall.

Theinternal construction of the boiler that may be used in a furnace of the character herein described may be of any usual force. As herein shown, the unconsumed gases or smoke pass rearwardly from the furnacechamber through a smoke conduit to the smoke-stack 27. The smoke-conduit may be arranged in any way; but, as herein shown, it consists of the passage-way under the boilers to the rear end and through the boiler-tubes 28, the pipes 29, and chamber 30. This invention is in no wise limited to a device having a smoke-conduit of any particular arrangement or form. After the smoke and unconsumed gases have passed through the boilers they are returned to the furnacechamber from the smoke-conduit. In the construction shown there are two returnconduits 3l, leading from the chamber 30 in the smoke-conduit down through the middle wall 14E, one to the furnace-chamber under one boiler and the other to the furnace-chamber under the other boiler. Said return-conduits 3l are provided with gates 32 for clos- 'lhe return-conduits discharge into the sides of the rear supplemental chambers 19. It is immaterial where the pipe enters said chamber 19. To cause the return of the smoke or unconsumed gases from the main smoke-conduit through the return-conduits, the following mechanism is provided: As shown in Fig. 4, the retu rn-conduit 31 leads from the chamber 30 of the smoke-conduit. At the point where the return-conduit 31 leaves the chamber 30 I mount a fresh-air conduit or inlet-pipe 33, that extends horizontaliy into the chamber 30 of the smoke-conduit, with its outer end open and regulated by a damper 34. The inner or what may be called the outlet end of said air-conduit 33 faces the return-conduit 31. In the form shown in Fig. 4 the airconduit extends into the return-conduit; but that is not necessary. The conduits 31 and 33 are preferably circular, and the air-conduit should be preferably on a line concentric with the return-conduit 31. At the inner end of the air-cond uit 33 I provide steamjets by an annular steam-chamber 35, with a large central opening for the passage through shown by the arrows in Fig. 1.

time.

it of the air from the air-conduit 33. Said steam-chamber 35 has outlet steam-ports 36, facing the return-conduit 31. When steam is introduced into the steam-chamber 35, it will draw the air from the outside through the conduit 33 and also draw the smoke and unconsumed gases from the smoke-conduit and force the air, steam, and smoke together back through the return-conduits 31 to the furnace-chamber. Any means may be provided for supplying the steam-chamber 35 with steam., and said steam-chamber may be made in any desired form so long as it is at the inner end of the conduit 33, and has an opening through it for the passage of air and an opening around it for the passage of smoke and unconsumed gases. The device that is herein shown and which I consider preferable has a larger steam-chamber 37, surrounding and concentric with the smaller steam-chamber 35 and connected therewith by radial arms 38, one of which is hollow to form a steam-passage 39 from the outer chamber 37 to the inner chamber 35. Steam is brought to said outer chamber through the pipe 40 and the passage-way 41. The pipe 40 leads from the steam-dome of the boiler. The outer steam-chamber 37 is concentric and of smaller diameter than the inlet to the returnconduit 31, so that there is a passage-way around said outer chamber 37 and another passage-way between said chamber 37 and the inner steam-chamber 35, through which the smoke and unconsumed gases are moved from the main smoke conduit and sent through the return-conduit 31. For this purpose the outer steam-chamber 35 has a series of outlet steam-ports 4t2, facing the returnconduit 31. From this construction it is seen that the jets of steam issuing from said steamchambers 35 and 37 will bringin a large supply of fresh air through the pipe 33 at the point where the smoke is diverted from the main conduit to the return-conduit and will move the column of smoke .through the return-conduit, the smoke, the air, and the steam uniting at the entrance of the returnconduit and commingling through the passage-way of the return-conduit 3l, as well as in the mixing or supplemental chamber 19 below the grate-bars, and they make a superheated and highlycombustible gas which passes up through the grate-bars from the rear portion of the furnace-chamberand makes a powerful heat, fully consuming all of the smoke and combustible particles, and the arches 24E deflect the powerful heat thus created and direct it against the boiler. This construction, having two chambers below the grate-bars of the furnace, supplies one with a natural draft and the other with an induced draft through the return smoke-conduits, as just described, and the arches tend to deflect the induced draft from the rear forward, as Means are provided above the grate-bars and at the forward portion of the furnace to supplya third IOO IIO

LS. O

furnace.

draft, that strikes horizontally across the furnace-chamber and causes the natural and the induced drafts just described to meet and thoroughly intermingle. This third draft consists chiefly of air brought from the outside, so that an ample supply of oxygen is provided, that tends to complete the combustion of all consumable material. `As will be observed, three means for obtaining oxygen or fresh air are provided in this apparatus-one through the ash-pit, another in the smokeconduit at a point where the smoke is returned, and the third over the fire-door of the This draft is supplied over the iiredoor by the following means: As shown in Fig. 7, a pipe 43 is placed with a funnelshaped air-inlet 44 leading from the outside and the steam-pipe 45 entering t-he pipe 43 at the junction of the air-inlet 44 and in line with the pipe 43. Said pipe 43 extends horizontally through the front wall in front of the fire-box and then returns, and the return portion thereof is provided with a number of outlet-tubes 46, that discharge into the firebox above the door. This construction makes a third draft entering the furnace-chamber, consisting of superheated air andstealn, for the air becomes heated in passing through the pipe 43 before it reaches the outlet 4G.

A manhole 47 is made in the `return-conduit 3l, as shown in Fig. 4, to give convenient access to the construction at the `junction of said return-pipe 3l and the main smoke-conduit for cleaning or removing the ports. To help in the matter of cleaning the steamchambers 35 and 37, they are made in two pieces, with overlapping lips 48 and bolts 49 for securing the two portions together. The arms 38, connecting the two steam-chambers, are secured only to one-half of each of said chambers, so that the fronthalf can be readily removed, and when removed the steam-cham-- bers can be easilycleaned. It may be added that the air-pipe 33 is not secured rigidly to the front wall of the smoke-chamber 30, but loosely, so that it can be slipped or removed for the better handling of the parts of the steam-chambers 35 and 37.

Two forms of thearches 24 are shown in` the device herein, as will be seen in Fig. 3. On the left-hand side the arch 24 extends entirely across the furnace-chamber over the full set of grate-bars; but that makesa heavy weight on the side Walls, and to relieve the weight on the side walls the arches may be made double, as shown in the right-hand side, and be centrally supported by the support 50. In order to distribute the dame and heat better, the bridge-wall and arches are made straight. This tends to prevent the ame or heat from gathering at the center, as is so common with some kinds of furnaces.

What is claimed to be the invention and to be secured by Letters Patent is l. In a furnace of the class described, a"

smoke-conduit, a conduit for returning the smoke and unconsumed gases from the smoke conduit `to the furnace chamber after the same have passed through the boiler, an airconduit in the smoke-conduit leading to the inletend of the return-conduit, and means for supplying a steam-jet at the outlet end of said air-conduit that directs the steam into the return-conduit.

2. In a furnace of the class described, a conduit for returning the smoke "and unconsu med gases to the furnace-chamberafter the same have passed through the boiler, an airconduit leading to the inlet-opening of the return-conduit, an annular steam-chamber at the outlet end of said air-conduit with outletports facing the return conduit, and means for supplying steam to said chamber.

3. In a furnace of the class described, a furnace-chamber, a smoke-conduit leading therefrom, a return-conduit leading from the smokeconduit back to the furnace chamber, an air-conduit extending transversely through the smoke-conduit with its outlet facing the return-conduit where itleaves the smoke-conduit, and a steam-jet directednto said return-conduit at the outlet end of the air-conduit for drawing air through the airconduit and the smoke and gases from the smoke-conduit and forcing them through the return-conduit.

alf

4. In a furnace of the class described, a

furnace-chamber, a smoke-conduit leading smoke-conduit back to the furnace-chamber,

an air-conduit with its outlet end near the` inlet end of the retu r11-conduit, asteam-chamber surrounding the outlet end of the air-conduit with outlet steam-ports facing the return-conduit, another steam-chamber surrounding the first-named steam-chamber with space between them and with outlet steamports facing the return-conduit, and means for supplying steam to said steam-chambers.

5. In a furnace of the class described, a furnace-chamber, a smoke-conduit leading therefrom, a returlrconduit leading from the smoke-conduit back to the furnace-chamber, an air-conduit with its outlet end near the inlet end of the return-conduit, means for supplying steam-jets consisting of two annular steam-chambers one concentric and connected with the other with space between` them and a steam passage-way from one steam-chamber to the other and the inner steam-chamber having an openin g through it ,and being secured to the outlet end of said air-conduit so the air from said conduit will pass through said inner steam-chamber, the outlet-ports from said steam-chambers facing said return-conduit, and means for supply-` ing steam to one of said steam-chambers.

6. In a furnace of the class described, a"

furnace-chamber, a smoke-conduit leading therefrom, a return-conduit leading from the smoke-conduit back to the furnace-chamber, means near the inlet to said return-conduit for supplying steam-jets consisting of annular steam-chambers formed of two separable ICO IIO

halves with overlapping lips at their joints and removable means for securing the parts of the steam-chambers together, and means for supplying said chambers with steam.

7. In a furnace of the class described, a furnace-chamber, a smoke-conduit leading therefrom, a return-cond uit leading from the smoke-cond uit back to the furnace-chamber, an air-supply pipe extendingloosely through the smoke-conduit with its outlet end facing the return-conduit, means at the outlet end of said air-conduit for diverting the air, smoke and unconsumed gases into the return-conduit, and a manhole in the return-conduit near the inlet end thereof.

8. In a furnace of the class described, a fire-box with grate-bars beneath it, two chambers below the grate-bars one behindthe other, a bridge-wall behind the second chamber and lire-box, an arch projecting forwardly from the upper part of the bridge-Wall, and an opening through the bridge-wall immediately below said arch thatdischarges immediately under the boiler.

9. In a furnace of the class described, a furnace-chamber having a lire-box with gratebars forming the bottom thereof, two chambers below said grate-bars one behind the other, means for supplying a natural draft through the forward chamber, means for maintaining an induced draft through the rear chamber, and means for introducing a third draft into the fire-box directed from the front toward the rear thereof.

10. In a furnace of the class described, a furnace-chamber consisting of a fire-box with grate-bars below it., two chambers below the grate-bars one behind the other, means for supplying a natural draft through the forward chamber, a smoke-conduit leading from the furnace-chamber, a return-conduit leading from the smoke-conduit back to the rear chamber under the grate-bars, means for making an induced draft through said return-conduit and said lrear chamber, a bridge-wall behind said rear cham ber, an arch projecting forwardly from the upper part of said bridgewall, and means over the door of the fire-box for introducing a blast of air and steam horizontally inward.

In witness whereof I have hereunto affixed my signature in the presence of the witnesses herein named.

CHARLES J. SHOEMAKER.

fitnessesz FLORENCE E. BRYANT, V. H. LooKwooD. 

